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><H1
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><A
NAME="INFOSCHEMA-ATTRIBUTES"
>34.6. <TT
CLASS="LITERAL"
>attributes</TT
></A
></H1
><P
>   The view <TT
CLASS="LITERAL"
>attributes</TT
> contains information about
   the attributes of composite data types defined in the database.
   (Note that the view does not give information about table columns,
   which are sometimes called attributes in PostgreSQL contexts.)
  </P
><DIV
CLASS="TABLE"
><A
NAME="AEN44728"
></A
><P
><B
>Table 34-4. <TT
CLASS="LITERAL"
>attributes</TT
> Columns</B
></P
><TABLE
BORDER="1"
CLASS="CALSTABLE"
><COL><COL><COL><THEAD
><TR
><TH
>Name</TH
><TH
>Data Type</TH
><TH
>Description</TH
></TR
></THEAD
><TBODY
><TR
><TD
><TT
CLASS="LITERAL"
>udt_catalog</TT
></TD
><TD
><TT
CLASS="TYPE"
>sql_identifier</TT
></TD
><TD
>Name of the database containing the data type (always the current database)</TD
></TR
><TR
><TD
><TT
CLASS="LITERAL"
>udt_schema</TT
></TD
><TD
><TT
CLASS="TYPE"
>sql_identifier</TT
></TD
><TD
>Name of the schema containing the data type</TD
></TR
><TR
><TD
><TT
CLASS="LITERAL"
>udt_name</TT
></TD
><TD
><TT
CLASS="TYPE"
>sql_identifier</TT
></TD
><TD
>Name of the data type</TD
></TR
><TR
><TD
><TT
CLASS="LITERAL"
>attribute_name</TT
></TD
><TD
><TT
CLASS="TYPE"
>sql_identifier</TT
></TD
><TD
>Name of the attribute</TD
></TR
><TR
><TD
><TT
CLASS="LITERAL"
>ordinal_position</TT
></TD
><TD
><TT
CLASS="TYPE"
>cardinal_number</TT
></TD
><TD
>Ordinal position of the attribute within the data type (count starts at 1)</TD
></TR
><TR
><TD
><TT
CLASS="LITERAL"
>attribute_default</TT
></TD
><TD
><TT
CLASS="TYPE"
>character_data</TT
></TD
><TD
>Default expression of the attribute</TD
></TR
><TR
><TD
><TT
CLASS="LITERAL"
>is_nullable</TT
></TD
><TD
><TT
CLASS="TYPE"
>yes_or_no</TT
></TD
><TD
>       <TT
CLASS="LITERAL"
>YES</TT
> if the attribute is possibly nullable,
       <TT
CLASS="LITERAL"
>NO</TT
> if it is known not nullable.
      </TD
></TR
><TR
><TD
><TT
CLASS="LITERAL"
>data_type</TT
></TD
><TD
><TT
CLASS="TYPE"
>character_data</TT
></TD
><TD
>       Data type of the attribute, if it is a built-in type, or
       <TT
CLASS="LITERAL"
>ARRAY</TT
> if it is some array (in that case, see
       the view <TT
CLASS="LITERAL"
>element_types</TT
>), else
       <TT
CLASS="LITERAL"
>USER-DEFINED</TT
> (in that case, the type is
       identified in <TT
CLASS="LITERAL"
>attribute_udt_name</TT
> and
       associated columns).
      </TD
></TR
><TR
><TD
><TT
CLASS="LITERAL"
>character_maximum_length</TT
></TD
><TD
><TT
CLASS="TYPE"
>cardinal_number</TT
></TD
><TD
>       If <TT
CLASS="LITERAL"
>data_type</TT
> identifies a character or bit
       string type, the declared maximum length; null for all other
       data types or if no maximum length was declared.
      </TD
></TR
><TR
><TD
><TT
CLASS="LITERAL"
>character_octet_length</TT
></TD
><TD
><TT
CLASS="TYPE"
>cardinal_number</TT
></TD
><TD
>       If <TT
CLASS="LITERAL"
>data_type</TT
> identifies a character type,
       the maximum possible length in octets (bytes) of a datum; null
       for all other data types.  The maximum octet length depends on
       the declared character maximum length (see above) and the
       server encoding.
      </TD
></TR
><TR
><TD
><TT
CLASS="LITERAL"
>character_set_catalog</TT
></TD
><TD
><TT
CLASS="TYPE"
>sql_identifier</TT
></TD
><TD
>Applies to a feature not available in <SPAN
CLASS="PRODUCTNAME"
>PostgreSQL</SPAN
></TD
></TR
><TR
><TD
><TT
CLASS="LITERAL"
>character_set_schema</TT
></TD
><TD
><TT
CLASS="TYPE"
>sql_identifier</TT
></TD
><TD
>Applies to a feature not available in <SPAN
CLASS="PRODUCTNAME"
>PostgreSQL</SPAN
></TD
></TR
><TR
><TD
><TT
CLASS="LITERAL"
>character_set_name</TT
></TD
><TD
><TT
CLASS="TYPE"
>sql_identifier</TT
></TD
><TD
>Applies to a feature not available in <SPAN
CLASS="PRODUCTNAME"
>PostgreSQL</SPAN
></TD
></TR
><TR
><TD
><TT
CLASS="LITERAL"
>collation_catalog</TT
></TD
><TD
><TT
CLASS="TYPE"
>sql_identifier</TT
></TD
><TD
>Not yet implemented</TD
></TR
><TR
><TD
><TT
CLASS="LITERAL"
>collation_schema</TT
></TD
><TD
><TT
CLASS="TYPE"
>sql_identifier</TT
></TD
><TD
>Not yet implemented</TD
></TR
><TR
><TD
><TT
CLASS="LITERAL"
>collation_name</TT
></TD
><TD
><TT
CLASS="TYPE"
>sql_identifier</TT
></TD
><TD
>Not yet implemented</TD
></TR
><TR
><TD
><TT
CLASS="LITERAL"
>numeric_precision</TT
></TD
><TD
><TT
CLASS="TYPE"
>cardinal_number</TT
></TD
><TD
>       If <TT
CLASS="LITERAL"
>data_type</TT
> identifies a numeric type, this
       column contains the (declared or implicit) precision of the
       type for this attribute.  The precision indicates the number of
       significant digits.  It can be expressed in decimal (base 10)
       or binary (base 2) terms, as specified in the column
       <TT
CLASS="LITERAL"
>numeric_precision_radix</TT
>.  For all other data
       types, this column is null.
      </TD
></TR
><TR
><TD
><TT
CLASS="LITERAL"
>numeric_precision_radix</TT
></TD
><TD
><TT
CLASS="TYPE"
>cardinal_number</TT
></TD
><TD
>       If <TT
CLASS="LITERAL"
>data_type</TT
> identifies a numeric type, this
       column indicates in which base the values in the columns
       <TT
CLASS="LITERAL"
>numeric_precision</TT
> and
       <TT
CLASS="LITERAL"
>numeric_scale</TT
> are expressed.  The value is
       either 2 or 10.  For all other data types, this column is null.
      </TD
></TR
><TR
><TD
><TT
CLASS="LITERAL"
>numeric_scale</TT
></TD
><TD
><TT
CLASS="TYPE"
>cardinal_number</TT
></TD
><TD
>       If <TT
CLASS="LITERAL"
>data_type</TT
> identifies an exact numeric
       type, this column contains the (declared or implicit) scale of
       the type for this attribute.  The scale indicates the number of
       significant digits to the right of the decimal point.  It can
       be expressed in decimal (base 10) or binary (base 2) terms, as
       specified in the column
       <TT
CLASS="LITERAL"
>numeric_precision_radix</TT
>.  For all other data
       types, this column is null.
      </TD
></TR
><TR
><TD
><TT
CLASS="LITERAL"
>datetime_precision</TT
></TD
><TD
><TT
CLASS="TYPE"
>cardinal_number</TT
></TD
><TD
>       If <TT
CLASS="LITERAL"
>data_type</TT
> identifies a date, time,
       timestamp, or interval type, this column contains the (declared
       or implicit) fractional seconds precision of the type for this
       attribute, that is, the number of decimal digits maintained
       following the decimal point in the seconds value.  For all
       other data types, this column is null.
      </TD
></TR
><TR
><TD
><TT
CLASS="LITERAL"
>interval_type</TT
></TD
><TD
><TT
CLASS="TYPE"
>character_data</TT
></TD
><TD
>Not yet implemented</TD
></TR
><TR
><TD
><TT
CLASS="LITERAL"
>interval_precision</TT
></TD
><TD
><TT
CLASS="TYPE"
>character_data</TT
></TD
><TD
>Not yet implemented</TD
></TR
><TR
><TD
><TT
CLASS="LITERAL"
>attribute_udt_catalog</TT
></TD
><TD
><TT
CLASS="TYPE"
>sql_identifier</TT
></TD
><TD
>       Name of the database that the attribute data type is defined in
       (always the current database)
      </TD
></TR
><TR
><TD
><TT
CLASS="LITERAL"
>attribute_udt_schema</TT
></TD
><TD
><TT
CLASS="TYPE"
>sql_identifier</TT
></TD
><TD
>       Name of the schema that the attribute data type is defined in
      </TD
></TR
><TR
><TD
><TT
CLASS="LITERAL"
>attribute_udt_name</TT
></TD
><TD
><TT
CLASS="TYPE"
>sql_identifier</TT
></TD
><TD
>       Name of the attribute data type
      </TD
></TR
><TR
><TD
><TT
CLASS="LITERAL"
>scope_catalog</TT
></TD
><TD
><TT
CLASS="TYPE"
>sql_identifier</TT
></TD
><TD
>Applies to a feature not available in <SPAN
CLASS="PRODUCTNAME"
>PostgreSQL</SPAN
></TD
></TR
><TR
><TD
><TT
CLASS="LITERAL"
>scope_schema</TT
></TD
><TD
><TT
CLASS="TYPE"
>sql_identifier</TT
></TD
><TD
>Applies to a feature not available in <SPAN
CLASS="PRODUCTNAME"
>PostgreSQL</SPAN
></TD
></TR
><TR
><TD
><TT
CLASS="LITERAL"
>scope_name</TT
></TD
><TD
><TT
CLASS="TYPE"
>sql_identifier</TT
></TD
><TD
>Applies to a feature not available in <SPAN
CLASS="PRODUCTNAME"
>PostgreSQL</SPAN
></TD
></TR
><TR
><TD
><TT
CLASS="LITERAL"
>maximum_cardinality</TT
></TD
><TD
><TT
CLASS="TYPE"
>cardinal_number</TT
></TD
><TD
>Always null, because arrays always have unlimited maximum cardinality in <SPAN
CLASS="PRODUCTNAME"
>PostgreSQL</SPAN
></TD
></TR
><TR
><TD
><TT
CLASS="LITERAL"
>dtd_identifier</TT
></TD
><TD
><TT
CLASS="TYPE"
>sql_identifier</TT
></TD
><TD
>       An identifier of the data type descriptor of the column, unique
       among the data type descriptors pertaining to the table.  This
       is mainly useful for joining with other instances of such
       identifiers.  (The specific format of the identifier is not
       defined and not guaranteed to remain the same in future
       versions.)
      </TD
></TR
><TR
><TD
><TT
CLASS="LITERAL"
>is_derived_reference_attribute</TT
></TD
><TD
><TT
CLASS="TYPE"
>yes_or_no</TT
></TD
><TD
>Applies to a feature not available in <SPAN
CLASS="PRODUCTNAME"
>PostgreSQL</SPAN
></TD
></TR
></TBODY
></TABLE
></DIV
><P
>   See also under <A
HREF="infoschema-columns.html"
>Section 34.15</A
>, a similarly
   structured view, for further information on some of the columns.
  </P
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